1. Field of the Invention
The present invention relates to a work vehicle such as a bulldozer.
2. Background Information
In recent years, there has been demand for cleaning of exhaust in work vehicles such as bulldozers from the viewpoint of the natural environment protection (refer to US Patent Application Publication No. 2010/0186381 A1). As a result, an exhaust treatment apparatus which is more advanced than a conventional muffler is mounted in the work vehicle. For example, such an advanced exhaust treatment apparatus includes a diesel particulate filter (DPF) apparatus, a selective catalytic reduction (SCR) apparatus, or the like. The DPF apparatus reduces particulate matter in the exhaust. The SCR apparatus reduces nitrogen oxide (NOx) in the exhaust. The exhaust treatment apparatuses are heavier and have greater capacity than conventional apparatuses.
As a method for providing a plurality of exhaust treatment apparatuses in a vehicle, there is a method where the DPF apparatus and the SCR apparatus are arranged above the engine so that the longitudinal direction of the DPF apparatus and the SCR apparatus is along the engine crank shaft direction as described in US Patent Application Publication No. 2010/0186381 A1. Since a crank shaft of the engine is arranged along the vehicle front and back direction in a typical bulldozer, the two exhaust treatment apparatuses are arranged so that the longitudinal direction of the two exhaust treatment apparatuses is along the vehicle front and back direction when this method is applied to a bulldozer. Since the lengths of the exhaust treatment apparatuses in the longitudinal direction are normally shorter than the length of the engine in the longitudinal direction, it is possible to avoid extension of the front and back length of an engine compartment due to the arrangement of the exhaust treatment apparatuses.